Exploder.



P. M. LBAVITT.

BXPLODEB.. APPLloA'rxon rum Nov. 29, 1911.

Patented July 29, 1913.

WITNESSES: @d

narran srATEs PATENT OFFICE,

' FRANK M, LEAVTT, 0F SMITH'POWN, NEW YORK, ASSIGNOR T0 E. W. BLISS COMPANY,

' F BROOKLYN, NEW YORK, A CORPORATION OF WEST VIRGINIA.

ExPLonan.

tenesse.

To all wlw/mif may concern Be it known that I, FRANK M. LEAvrr'r., a citizen of the United States, residing in Smithtown, in the county of Suffolk and State o'.. New York, have invented certain new and useful Improvements in Exploders, which the following is a specication.

@his invention relates to exploders operated by a :fluid under pressure.

kThe invention has been primarily designed and adapted for use in automobile torpedoes a means for igniting vthe fuel in the heater (technically called the superheaterl) for heating the compressed air in its passage from the air Hash or compressed air reservoir to the turbine or other motor engine. In such heaters the igpition of the fuel Vmust be accomplished during or consew quent upon the launching of the torpedo. The launching operation opens the throttle valve, which admits compressed air to the engine, and consequently starts the engine andv propellers revolving, which in an overwater launch results in bringing the pro eliers into action While the torpedo is moving through the air and before it enters the water. It is desirable that the increased energy imparted to the air by heating it be made effective at as nearly the instant of suhmersion as possible., The feeding of alcohol or other liquid fuel which is sprayed into vthe heater, commences valso consequent upon the launching operation, being commonly performed by the forcing in of the fuel under air pressure, which pressure resultsfrom the opening of the throttle valve. The ignition is commonly effected by means of a cartridge the cap of which is exploded automatically in or consequent upon the act of launching, and to delay the ignition it is customary to use a cartrid e of smokeless powder, which burns slow y enough to prolong the ignition `tor a certain time. It is necessary to delay the igniting eect until the infeed of liquid fuel to the heater shall have been started and has become adequate, as otherwise the ignition might fail.

The pr sent invention provides an exploder which instead of acting immediately upon.

Specification of'Letters Patent.

Application filed November 29, 1911.

4*Patented July 29, 1913. SerialvNo. 662,988.

the turning on of fluid pressure, has a delayed action such that the explosion is deferred for an appreciable or predetermined time after the admission of Huid pressure. As applied to a torpedo the delayed action may amount to from one-quarter second (or less) to vone second (or more), bei Sullicient to certainly give time for the goed of liquid fuel to have become so far started as to insure that the fuel shall have reached the heater, and that a continuous inflow of the Huid shall thereafter be maintained.

The present invention provides a hammer for striking the percussion cap .of the cartridge, which hammer is operated -by a piston or plunger (preferably formed integrally with the ammer), .which piston moves in an air cylinder in such manner that when the air pressure is Afirst admitted it causes the piston to execute a slow preliminary movement by 'reason of the re' stricted admission of air, which movement consumes sufficient time to accomplish the desired delay, whereupon the piston uncovers a larger admission opening whereby the compressed air is admitted behind it at such rate as to cause it to move at high velocity so that the hammer is caused to strike the requisite blow against the cap for accomplishing the ignition.

,The preferred embodiment of my invention is shown in the accompanying drawin Wherein,- Y

igure 1 is a longitudinal mid-section of a portion of the after body of an automobile torpedo showing the heater and its ac cessories in elevation; Fig. 2 is a vertical mid-section of the heater and exploder. on a larger scale; Fig. 3 is an .elevation of the exploder detached.

Referring to Fig. l, A is the shell or hull of the torpedo; B is the air llaskor compressed air reservoir; C is the vturbine, or other engine or motor which drives the propeller shaft D; E is the air heater; F is the fuel tank; G is a reducing valve, which may also be the starting valve.

Upon the opening of the starting valve, compressed air is a mitted from the reservoir B through the pipe a, which `pressure is reduced by the reducing valve G, and the air then passes by pipe b to the heater E and thence by pipe c to the engine. Liquid fuel such as gasolene or alcohol, is supplied in the tank F, and this receives air pressure through a pipe d by which the fuel is driven out through pipe c and sprayed into the heater through nozzle The details of these several apparatus are not shown, being well understood.

The exploder H to which the present invention pertains, is inserted in the heater E at any convenient location, as by introducing it through a neck g which may be formed at one end of the heater. It is desirably rendered accessible through a plug h in the torpedo shell A, whereby the exploder may be removed and replaced.

For operating the exploder, compressed air is admitted t0 it through any suitable air duct, as for example the pipe z' (Fig. 1) which may Aconnect with the valve Gr as shown, and thereby be put in communication with the source of air at high pressure; or any other connection may be made whereby when the compressed air is admitted to the heater air pressure is simultaneously admitted to the exploder.

The' exploder comprises a shell which at one end has a removable section k adapted to receive an ordinary blank cartridge I having the usual percussion cap; and which is formed internally with a chamber or cylinder m in which moves the piston or plunger p, this cylinder being closed by a plug o. The hammer or tiring pin r is arranged to slide through a guide portion in the shell j, and-when projected its pointed end strikes the cap. 1t is operated by the piston p, preferably by its being connected directly thereto or formed integrally there- `with. The parts are shown in the initial or preparatory position. To hold them in thisI position any resistant means may be provided which is adapted to afford enough resistance to prevent accidental displacement of the piston and firing pin during handling. The means shown consists of a key' s which consists of a small wire of copper or other suitable metal inserted through coinciding holes in the shell and tiring pin, so that the tiring pin can be displaced only by a pressure sufficient to shear this wire key.

As shown they piston stands initially in approximately the middle of its cylinder. In this position it blocks a direct air port t which communicates with the air inlet'pipe z'. Another air port u, however, yis provided, which leads air from the air inlet to the other end of the cylinder m. This air duct is preferably a contracted duct. The piston is not made leak-tight, but is made a suffipermit a slight leakage of air around it. 1f too tight to afford the requisite leakage, a

small groove 'e may be formed upon the periphery of the piston through which air leakage may occur.

The operation may now be understood. 'lhe explotler being primed and in place in the heater with its parts in the osition shown in Fig. let us suppose t at -the torpedo' is launched, by which operation compressed air is automatically' admitted to the heater and engine. At. the same instant compressed air is admitted through the pipe z' to the exploder. The port t being closed this air can only enter the exploder through the end port 11. Thus entering, it presses against the exposed annular surface of the forward end of the piston around the ha mmcr 1, and the pressure thus exerted against the piston is sutlicient to instantly shear the pin s. The piston thenmoves rearwardly toward the plug g; since behind the` piston there exists air at approximately atmospheric pressure only; this movement occurs quickly, and until the air which is behind the piston is compressed to the same pressure as that on the opposite Side which impels the piston, whereupon the piston is stopped by the cushion thus afforded. For a.

moment it dwells in this position. Thereupon by leakage around the piston or through the groove o as the case may be, the

equilibrium `is disturbed by reason of the air acting upon the full area ofthe back of the piston, whereas on the frontthereof it` acts only on the annular areal around the hammer fr which acts as a piston rod.` Consequently the pressureback of the piston preponderates, and the piston consequently moves forward, this movement occurring, however, at a rate which is determined by the rate of leakage past the piston. This slow movement occurs until the piston advances enough to uncover the direct port t, whereupon a comparatively unrestricted flow of air is admitted to the rear of the piston, and acting against the differential or unbalanced area thereof (being the area` of the hammer r) the air thus admitted is movement to strike the 11ammer blow,aifords A, ample ,time after the admission of com--- pressed air for the latter to institute the infeed of fuel to the heater. The ignition of the fuel by the flame' blowing out from the cartridge is thus assured. `Inasmuch as some leakage occurs around the hammer 1' where ciently free or loose fit with the cylinder to t it has its sliding seat m the exploder shell1 titi a e.mali hiet if; ia provitleti in the eftion .la to permit thisl leakage to {If-reape: as otherwise it would :,tteonmlate :tml exerty :s pre,` .otre aggjaiimt the pointed emi ot the hammer. To again me the explotlel. it. is hotliy nn-A serew'wl from its: .wat in the riveli' 5,/ of the heater. ami the aeetion 1'.' ia miatzivwetl from it: the earritlgty\hell i then removed from thia section am! a new eartrhlge inaex'tefi. The hammer is reetoreil to its original Centr: l position, aml the #hear he); or wire in pushed ont of ite; :foi-liet :imi replmetl by a .new hey of s-'niiahle wire. The i iii then si he 'ewefl hwk into the net-'iq ot t heater ami ia really t'or the next operation. By meantI of this1 eonstrnetion ot explotler a retardation of from one to two seconds, or

even longer, ean easily be obtained.

A\n important advantage ot' tleiavmg the ignition i that in ease of an over-water it pievent the raving et" the engine. While, heliorpenloisheing latmrhell through the air i :s engine is artetl, ami as, tinl propeller'\ emoimter oniy the rezistaoee oi the air. ila-x are tiiahle to race; this raving hor'- ever iaiaol serions if the eomprefewt air is etlmtetl froid to the engine; hm it' the .ialiiirh :eater tieejini to art. to heat the ait before he to petlo enters the water, he energy of the air o greatly increased as to ranse emitan anti detrimental rat-ing of the pro itf tleiaying the ignition long;r i' ere, that'the torpetlo ahall enwat'er before any aerimis heating of ter the the air shall rommeiae` thif,A 'piaxi-tieally ove aimee the nmh'ie Speeding or raving' ot the engine.

My invention is ne? limited to the eon- Htrnrtion shown, hut, nay he mothhetl to a greater or less extent without depnrtin;5 from itay eaeential features# whirl; are tet forth :zi the elainm.

:t ma preswal ein porta for operate it. sanl of eoinpi'e'eeti lit; y" tow oi air to retard the preliniinary mote ment oi' the hammer. 11ml to atlmit milisepie'itv f more 1H niet! -f-. lo mimit primarily a minnte er tlow to impel the hammer piston, and the other atlaptetl to nneover atthe eral ot' sim-h preliminary movement to admit a. larger flow of air to impel the piston foreihlj.' to the tiringpfsition.

4. An exploiter comprising a easing formed. with a piston ehamlier, a piston moving;r therein having a stem on one .side paSwing out through the eml ot' saitl ehamlier, ami air ports entering said chamber the one admitting nir on the front l#itle of the pi ton to art against its lesser area` whereby the leakage of air to the opposiie aille. of the piaton valises the piston to exe ente a slow preliminary movement, an l the other port aflapteil to he nneoveretl at the emi of Snell preliminary movement to admit air *freelyv to the rear l itle ot' the piston tot impe] it foreihly to the tiringV position.

5. -ln explotler eomprising a Casing -rme|| with a piston ehamher` a pibton movin; therein havingr a stem on itl forwartl ille passing ont through the Jfront enti otl saifl eliamher. the piston initially oeymoving an intermediate position in saifl eliamier` with reeistant means for holding it in #oeh position, antl air portaA entering aait! ehamher. the on` atlmittimgr air on the iront, lille of the piston to art against its lesser area whereby when air pi'essnre-is turned on it overeomea` the resistance of said reeistant meam anti moves the piston l ackward, after whieh the leakage of air to the opposite aille ot' the piton (muses it to eXeente a lslow preliminary forvzrtl movement, aml the other port adapted to be uncovered at the emi of sneh preliminary movement t0 admit air freely to the rear sitle of the piston to impel ity foreihly to the firing positon.

t3. An explorler comprising a compressed air-operated hammer having means for adi mitting air to canse, the -hammer to execute :m initial haeluvartl movement preliminary to its forward blow, whereby to delav thee explosion. v

7 An exploder comprising a pressure-:101 toatetl piston and a easing therefor having` ali-air port nneovered by thepistonin its movement, with a port admitting a restricted flow for causing a slow, preliminary armement whereby to retard the action of the explotler.

v An explodercomprising a pressure-ac mated piston and a easing' therefor having a larger aml a smaller air port, the latter azlaptetl to admit a minute, flow to canse, a sitow, preliminary movement of the, piston, and the former arranged to he uncovered hy the piston at the end of auch movement and thereupon to atlmit an augmented tlow to impel the piston forcibly forward.'

Si. An explotier comprising .a pressllreaxemated piston and a easing therefor having a larger air port uncovered by the piston during its movement, and restricted pm'tS, the latter' adapted to admit u minute flow in front, 0f the piston to force it initially haekward :1nd subsequently hehind the piston to force ity fniwnid with :1 slow', preliminary movement until it, uncovers Suid larger poi-t.

In Witness whereof, Vl have hereunto FRA f lVitnesseS:

H. C. SEAMAY/ JOHN D. MGINrYRn. 

